INVENTION OF PENCIL 

In the 16th century, lumps of a strange black substance were found beneath the hillside of Borrowdale, a valley in the Lake District of northern England. Although the mineral looked like coal, it did not burn; and it left a shiny, black, easily erased mark on a writing surface. Initially, the substance had a variety of names—black lead, wad, and plumbago, meaning “that which acts like lead.” Because it had a greasy texture, people wrapped chunks of it with sheepskin or short sticks of it with string. No one knows who first thought of putting black lead into wooden holders, but by the 1560’s, primitive pencils had reached the European continent.

Soon black lead was being mined and exported to meet the demands of artists; and in the 17th century, it was being used practically everywhere. At the same time, pencil makers experimented with black lead to produce a better writing instrument. Pure and easily extracted, the Borrowdale product became a target of thieves and black marketers. In response, the British Parliament passed a law in 1752 making the theft of the material punishable by imprisonment or banishment to a penal colony.

In 1779, Swedish chemist Carl W. Scheele made the surprising discovery that black lead was not lead at all but a soft form of pure carbon. Ten years later German geologist Abraham G. Werner named it graphite, from the Greek graphein, “to write.” Yes, contrary to their name, lead pencils actually contain no lead at all!

The Pencil Comes of Age

For many years English graphite cornered the pencil-making industry because it was pure enough to use without further processing. Since European graphite was inferior, pencil manufacturers there experimented with ways to improve pencil leads. French engineer Nicolas-Jacques Conté mixed powdered graphite and clay, shaped the mixture into sticks, and fired them in a kiln. By varying the ratio of graphite to clay, he was able to make leads that produced different shades of black—a process still in use. Conté patented his discovery in 1795.

In the 19th century, pencil making became big business. Graphite was discovered in a number of places, including Siberia, Germany, and what is now the Czech Republic. In Germany and then in the United States, a number of factories opened up. Mechanization and mass production drove prices down, and by the start of the 20th century, even schoolchildren were using pencils—unpainted “penny pencils,” as they were called in the United States.

The Modern Pencil

With many billions manufactured worldwide each year, the pencil has become a sophisticated, versatile writing and drawing instrument. A typical wooden pencil can draw a line 35 miles long and write 45,000 words. Made of metal or plastic, mechanical (or, propelling) pencils hold thin leads that never need sharpening. In the place of graphite, colored pencils use dyes and pigments that come in dozens of colors.

Versatile, robust, simple, and efficient, the lowly pencil shows no signs of obsolescence. Hence, for years to come, whether at home or at work, you may still hear someone ask, “Does anyone have a pencil?”

HOW DOES THE LEAD GET INTO THE PENCIL?

A solution of finely ground graphite, clay, and water is forced through a narrow metal tube and comes out looking like a long string of spaghetti. After being dried, cut, and fired in a kiln, the lead is immersed in hot oil and wax. The wood, usually cedar, which is easily sharpened, is sawed into slats—planed and grooved pieces of wood—half a pencil thick. The leads are inserted into the grooves on one slat, and a second slat is glued and pressed on top of the first. When the glue dries, the individual pencils are cut apart. After shaping, sandpapering, painting, and stamping with the manufacturer’s trademark and other details, the now seamless pencil is ready for use. Sometimes an eraser is attached to one end.

TYPES OF PENCIL, AND WHAT IT IS USED FOR.

To select the pencil you need, note the letters or numbers printed on the side of the pencil. These indicate the degree of hardness or softness. Softer leads leave a darker mark.

HB is a versatile, medium-grade lead.

B denotes softer leads. A number such as 2B or 6B denotes the degree of softness—the higher the number, the softer the lead.

H denotes harder leads. The higher the number—2H, 4H, 6H, and so on—the harder the lead.

F stands for fine point.

Some countries use different systems. In the United States, for example, the number 2 pencil is equivalent to an HB. In that system the higher the number, the harder the lead.

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